A Lempel-Ziv Compressed Structure for Document Listing

Document listing is the problem of preprocessing a set of sequences, called documents, so that later, given a short string called the pattern, we retrieve the documents where the pattern appears. While optimal-time and linear-space solutions exist, the current emphasis is in reducing the space requirements. Current document listing solutions build on compressed suffix arrays. This paper is the first attempt to solve the problem using a Lempel-Ziv compressed index of the text collections. We show that the resulting solution is very fast to output most of the resulting documents, taking more time for the final ones. This makes this index particularly useful for interactive scenarios or when listing some documents is sufficient. Yet, it also offers a competitive space/time tradeoff when returning the full answers.